Questions tagged [rom]
For questions about Read Only Memory.
76
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Where to obtain 3c509b empty boot ROM chip?
I'm planning to write iPXE to boot ROM of my 3c509b to enable HTTP booting on my old computer.
What is the type of the ROM chip and where would you obtain it? It's 28 pin connector, please see picture ...
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4
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Did anybody use PCBs as macro-scale mask-ROMS?
Early on, even fairly small ROM's were quite useful. For example, you could fit a minimal upper-case only font for a terminal into something like 256 bytes. And that's a scale that a human could lay ...
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Why did the Nintendo GameBoy Color make the name of any game to have a specific checksum?
Inside of the GBCs Cartridge header there is the metadata for the game and the Nintendo logo.
The program that runs on boot (the BIOS or Boot ROM) checks the checksum of the Nintendo logo, and always ...
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Dump Mask ROM on MAB8421
I am trying to find a way to dump the rom contents of several MAB8421 microcontrollers. I know that on many 8048 MCUs, you can use the external access pin to dump the rom, but the 8421 doesn't have ...
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Can you read the character definitions (font) in an Apple II using PEEK in Applesoft BASIC?
Can you read the character definitions (font) from ROM in an Apple II using PEEK in Applesoft BASIC? You can do this on some other computers e.g. Sinclair ZX81, Commodore 64, and Amstrad PC1512, but ...
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What type of memory was used in N64 and GBA cartridges?
I would like to know if consoles like the N64 and GBA used masked ROMs or some kind of eFuse based ROM, or if they were some kind or flash or EEPROM based memory. I've read that both consoles had ...
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How to assign code to different PRG-ROM banks on an NES ROM using ca65/ld65
A similar question was asked here but I read it and didn't really understand the solution.
What I'm trying to do here is make an NES ROM that uses Mapper 24, aka Konami VRC6 Version 1 (the one used by ...
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Problem with hackrom on real GBA cartridge
This is a problem that has brought me headaches, so I will try to explain as best as possible.
I have flashed with a Gbxcart several GBA ROMs in real cartridges (repro), working without any problem, ...
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1
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Can you switch the ZX81 ROM to RAM w/o write protecting it and still use ZX81 BASIC?
I built an external 8K RAM circuit that replaced the 8K ROM of Sinclair ZX81 and I also pulled out address lines from the ULA (dogsbody) so that character generation worked. I wrote a small machine ...
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2
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What does it mean to byte swap or split a ROM image?
I'd like to understand: What does it mean to "byte swap" when burning kickstart or extended ROMs? Is it the same as "splitting" the ROM? How is it done and why?
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How many kinds of mass-producible ROM is avaliable before 1970? [duplicate]
Back in the days before mask ROM (when invented?) we got core rope memories, or Little Old Ladies memories, which required lots of human labor to build.
Were there any kinds of ROMs which were ...
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2
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C64 KERNAL Loading into I/O space [duplicate]
On a Commodore 64, if I Load "*",8,1 and the file's address (first two bytes on disk) is $D000, will it load to the RAM under the I/O space?
In other words, does the KERNAL loader properly ...
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1
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Did the Apple 1 cassette interface card have its own ROM?
According to this page, the Apple 1 monitor program was located in addresses $F000-$FFFF, a ROM program to use the optional cassette interface card was at addresses $C100-$C1FF, and the peripheral ...
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1
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How did Woz get the Apple 1 monitor program into ROM?
Unlike the Apple ][, the Apple 1 never had BASIC in ROM. The Apple 1 booted into a monitor program, which enabled the user to type in machine code for a program (as Steve Wozniak often did), or load ...
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Cheapest type of Read-Only Memory allowing Random access before Year 1970
Back in the 50s and 60s people had:
random access, read-write memories like Magnetic Cores.
sequential access, read-write memories like Delay Lines and Magnetic Tapes.
And:
sequential access, write ...
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Hitachi HD630x executable format
Can anyone tell me what executable format the Hitachi HD630x series of MPUs used?
I'm looking to disassemble (out of curiosity) a binary for the Hitachi HD63A03XP microprocessor. In case anyone is ...
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2
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CPU slaves on a PCI card to retrofit single processor to multiple processors. Any ideas how? [closed]
My desktop computer is no longer manufactured and no longer supported since more than 18 years ago. It was a very expensive top of the line business computer back in the day. I like it and wish to ...
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8
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Why is EEPROM called ROM if it can be written to?
Is there a historical reason? Since it is rewritable it isn't read only by definition, so why call it so?
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Macintosh II ROM Replacement
I'd like to upgrade my Macintosh II to FDHD, I have a SWIM chip (to replace the WIM chip), but don't know how to burn the ROMS.
The upgrade process I'm trying to do is described in the book: "...
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Did any SNES games use the fast ROM?
According to the transcript at https://fabiensanglard.net/another_world_polygons_SNES/
... I could get the software running again to run at about 30 frames per second if of course I'm using a fast ...
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How can a Game Boy game "glitch-inherit" the music from a different game like this?
Just now, I saw a stream of a person playing Game Boy games. The technical setup is like this:
Real American SNES.
Real Super Game Boy 2. (Only released in Japan; fixes the speed bug in the Super ...
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Algorithm for Apple IIe and Apple IIgs boot/start beep
What is algorithms use for boot/start sound (when turn on computer) in Apple IIe and Apple IIgs? I can't find information about Apple boot sound algorithms or where in computer ROM store either ...
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How to flash CDTV extended ROM using development board
I have a CDTV ROM development board, and I know it is possible to flash it using floppies. How to make such floppy with a custom rom?
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advice for retrieving functions and tables from intel 8061/8065 bin file (reverse engineering) from Ford EECV ECU
I have under my disposal some Ford EECV bin files and my goal for the next few weeks is to retrieve the functions and tables and plot them out before going onto DIY hardware . .
Does anyone know which ...
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How likely is it that a ROM could be "corrupted" resulting in visual artifacts during gameplay? [closed]
I watch a lot of retro game streams. Frequently, whether they are running on a software emulator, hardware emulator (Retron 5 or whatever), or an Everdrive, whenever there is some weird glitch in the ...
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Why are there no actual complete and 100% verified/vetted ROM collections still? [closed]
Recently, I've been searching far and wide to collect, in digital form, the exact games that I owned as a child, or had temporarily, or rented/borrowed/played at somebody else's house, or never really ...
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Every single ROM in my collection has the wrong SHA1 hash according to No-Intros
I have a collection of ROM files for the NES, SNES, Nintendo 64 and others. These ROMs match exactly those games that I own or owned growing up.
Recently, I found out about the "No-Intros" ...
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Why is Sega Saturn mysteriously missing from No-Intros.org's hash database? [closed]
https://datomatic.no-intro.org/index.php?page=download
This website has the worst, most cryptic and broken interface I've ever seen in my life, but eventually, I managed to download a big archive ...
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What does "ByteSwapped" and "BigEndian" refer to in the context of video game ROMs?
I have found two different sets of Nintendo 64 ROMs with the same games (which, of course, I physically own). One is labeled "ByteSwapped" and the other "BigEndian". What exactly ...
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How can I get MAME to run modified ROMs whose checksums don't match the originals?
In the aftermath of the question about running the arcade Pac-Man ROM on a Sinclair ZX Spectrum I discovered that about the same time that was done, somebody else did the reverse, porting a classic ...
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What is the purpose of ROM switcher mods in CDTV
I've seen a lot of information on CDTV ROM switchers, but it is still unclear to me what is the actual purpose of it. As I understand it allows some compatibility with A500 games, but this disables CD ...
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How was the second bank of Apple IIc ROM accessed?
The original Apple IIc had a 27128 16 KB ROM mapped into the
$C100-$FFFF range (the $C000 page was decoded for I/O). According to
the Apple IIc Technical Reference Manual the ROMEN1*
and ROMEN2* ...
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3
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Decoding Logic and Memory Systems for 8-bit computer - 64K address space
I am creating a minimal Z80 computer with serial output on a breadboard. I have kind of moved up from the last question, where I was executing instructions on Z80 using specific connection of ...
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"Genesis Lock-On Technology" to change the language of a Famicom game
I want to create a cartridge similar to Sonic & Knuckles or a Game Genie so that the text files loaded from the ROM or DEPROM of an original Famicom cartridge can be replaced with alternate ...
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1
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How do you switch ROM banks on Gameboy MBC2 Cart with INLRetro dumper
I have an INLRetro cart dumper. The software for the device is incomplete and in beta form. I've been able to dump Tetris and it works (because it's ROM fits into bank 0). When I attempt to dump ...
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Can you program an arcade game and have MAME or another emu run it?
I know Mame works with drivers for each game or hardware, and it checks for specific ROMs, and I guess it might check also for some checksum to verify the ROMs integrity.
Is there some way you could ...
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ZX Spectrum: What is the "T" state value, with reference to sound?
I have that awesome book - Zx Spectrum ROM Disassembled (correct the title if I got it wrong), where the author wrote about the audio code in the ROM and referring to "T" state, "... T200... T5000, ...
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What is the Circuit for a 16K or 32K MSX computer cartridge?
This question is about the old MSX-1 computers. I have a game I wrote, as a ROM file, and I now want to play it on a real MSX computer by putting the game into cartridge form. The game has been ...
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Can the Nintendo 64 run code directly from ROM?
I've read that the usual way to execute code on the N64 is to use DMA to copy it from ROM into RAM, and then run from RAM.
However, it seems that the contents of the ROM are directly visible to the ...
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Is it safe for C64 cartridges to respond to read and/or write requests on "unmapped" addresses?
According to the C64 wiki, asserting G̅A̅M̅E̅ on the
cartridge port (and not asserting E̅X̅R̅O̅M̅) of the C64 leaves three
blocks of the C64 address space "unmapped": 28 KB @ $1000 (otherwise
RAM), 8 ...
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Dimensioned drawing of 64-pin SIMM?
I am looking for a dimensioned drawing of a 64-pin SIMM PCB like the ones used in the Macintosh II series for the ROM SIMM. I looked in Guide to the Macintosh Family Hardware and Designing Cards and ...
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Patch BBC Master ROM using Sideways RAM?
I have a BBC Master 128 with the standard ROM installed. This includes ADFS v1.50 in slot "D". I want to replace this ADFS in ROM with a patched version, loaded from disk, into Sideways RAM. It is a ...
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C64 cartridge emulation with ATmega
As a personal project I had the idea to create a custom cartridge for my Commodore 64 and use an ATmega 1284p microcontroller to emulate eproms and/or custom chips.
Basically my idea is similar to ...
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Expanded Ram Options for the TRS-80 Model 100 possible into the megabyte range?
I have a trs-80 model 100. I have all the option rams used. I've seen some quite useful ideas from other collectors on the internet for other TRS-80 model computers of using mouser electronic parts to ...
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Does fast page mode apply to ROM?
Starting with the 4116, RAM chips from the late seventies supported fast page mode, where if you were reading nearby – particularly, successive – words, you didn't need to supply both row and column ...
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What was the purpose of GROM (vs ROM) in the TI-99/4a?
The TI-99/4a had a cartridge slot on the front of the computer which accepted "solid state cartridges" (as TI called them). These cartridges would typically contain ROM (Read Only Memory) like many ...
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List of Intel microchips
Where could I find a list of all of the microchips released by Intel, including microprocessors, Rams, roms, storage devices. Etc.
I have checked Wikipedia, and they have the processors, but not any ...
user11220
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How do arcade ROMs work
The way I understand it, ROMS are like virtual games, and emulators are like virtual game consoles, or handhelds. What I don't understand is how there are ROMs for arcade games, which don't have ...
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Can I trigger the Amiga ROM debugger from the boot prompt?
Suppose I have an Amiga computer without any working boot disks. Is it possible to trigger the built-in ROM monitor (RomWack or SAD, see https://theamigamuseum.com/amiga-kickstart-workbench-os/guru-...
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What home computer was the first to use a external ROM cartridge?
When was the external ROM cartridge first used and what home computer was the first to use it?
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